furl vs swirl

furl

verb
  • To lower, roll up and secure (something, such as a sail or flag) 

swirl

verb
  • To twist or whirl, as an eddy. 

  • To be arranged in a twist, spiral or whorl. 

  • To circulate. 

noun
  • The upward rushing of a fish through the water to take the bait. 

  • A twist or coil of something. 

  • A whirling eddy. 

How often have the words furl and swirl occurred in a corpus of books? (source: Google Ngram Viewer )